N.Y. Comp. Codes R. & Regs. tit. 17 § 2C.127
Option:
01 The Sign Marker (NYW7-15) (see Sign Drawing SD-W40) may be used to emphasize regulatory and warning signs, particularly newly-installed regulatory and warning signs.
Standard:
02 The Sign Marker shall be fluorescent orange, fluorescent red-orange, fluorescent yellow, or fluorescent yellow-orange, and shall be retroreflective.
Guidance:
03 Where used with a regulatory sign, two Sign Markers should be placed side-by-side in a symmetrical pattern above the sign, either adjacent to one another, or separated.
04 Where used with a warning sign, two Sign Markers should be placed in a symmetrical pattern above the sign, either adjacent to one another above the upper corner, or separated and placed individually along the top edges of the sign.
N.Y. Comp. Codes R. & Regs. Tit. 17 § 2C.127